import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        String str1 = in.nextLine();
        String str2 = in.nextLine();
        Map<Character,Integer> hash = new HashMap<>();
        for (int i = 0; i < str2.length(); i++) {
            hash.put(str2.charAt(i),1);
        }
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < str1.length(); i++) {
            char c = str1.charAt(i);
            if(!hash.containsKey(c)){
                stringBuilder.append(c);
            }
        }
        System.out.println(stringBuilder);
    }
}